Plug-rotating cam for breech mechanisms.



D. F. ASBURY.

PLUG ROTATING CAM FOR BREECH MEGHANSMS.

APPLICATION mu) JULY 21.1915.

1,186,265. Patented June 6, 1916.

2 SHEETS-SHEET I.

0 I Witnem 1y D F. ASBURY.

- PLU G ROTATING CAM FOR BHEECH MECHANISMS.

Patented June 6, 1916.

2 SHEETS SHEEI 2.

APPUCATION FILED JULY 21,1915.

grwenkw UNITED STATES PATENT OFFICE.

DORSEY FROST ASBURY. OF WASHINGTON. DISTRICT OF COLUMBIA. ASSIGNOR TO UNITED STATES ORDNANCE COMPANY. OF WASHINGTON. DISTRICT OF COLUMBIA. A CORPORATION OF VIRGINIA.

PLUG-ROTATING CAM FOR BREECII MECHANISMS.

1 .1so,2o5.

Application filed July 21, 1915.

'lb 11/] who!!! if 'IIHIII/ con ern Be it known that l. Donsnv F. Asniinv. a citizen of the l nited States. and resident of the city of Washington. in the District of tolumbia. have invented certain new and useful Improvements in llug- Rotating tams for Breech .\lechanisms. oi which the following is a spmification. I

My invention relates to breech mechanisms and more especially to plug rotating cam devices therefor.

The principal objects of my invention are to prevent skidding of the roller element of the cam device on the cam face: to so arrange the elements of the cam device as to permit of the element carrying the cam face being mounted on the plug and fitted into an unused blank space between the plug threads in a manner that will not interfere with the swinging of the plug into the bushing: to arrest the whirling movement of the plug about the hinge of the carrier and then hold the plug during its rotation and thereby prevent the forward end of the plug flying or springing toward the hinge side of the gun and striking blows thereagainst: to prevent the forward slope of the plug threads and the rear slope of the breech bushing threads from being in hard contact and thereby eliminate the friction between these slopes during rotary movement of the plug; to prevent chattering of the plug and bushing threads while engaging; to eliminate the tendency of the plug to lift or lower dur ing operation of the cam device; and to eliminate stress and friction at the plug spindle on the carrier.

Briefly stated, the breech mechanism by which the foregoing objects of my invention are accomplished comprises a hinge carrier adapted to be swung in any suitable manner and upon which is rotatably mounted a breech plug. Cam devices are disposed diametrically opposite with respect to the plug and simultaneously operate. as the plug is swung home. to impart locking rotation thereto. Each of these cam devices consists of a member mounted on the plug and pj evided with a cam face. and a roller mounted on the gun for cooperation with the member and having its axis of rotation disposed at an angle to the breech face and substantially in a line extending through the pivotal axis of the carrier. The

Specification of Letters Patent.

Patented June 6, 1916.

Serial No. 41.062.

member of the cam device on the side of the plug remote from the pivotal axis of the carrier has its cam contact surface extended whereby the related roller will remain in engagement therewith to arrest the whirling movement of the plug about the hinge of the carrier and then hold the plug until the same has substantially completed its locking rotation.

In the drawings chosen for the purpose of illustrating my invention. the scope whereof is pointed out in the claims, Figure l is a view in elevation of the breech end of a gun embodying my invention, the carrier being broken arvay and those parts of the breech mechanism n t essential to the, invention omitted for the sake of clearncss: Fig. 2. a section on the line 2 2 of Fig. l with the parts in the position they would occupy at the beginning of the closing rotation of the plug: Fig. 3. a section on the line 3 4) of Fig. 2: and Fig. 4 a section on the line al -1 of Fig. 2.

Referring to the drawings A the gun. and A the breech bushing provided with interrupted threads A It is the breech plug having interrupted threads l3 forming resulting blank spaces B, the threads B being adapted to cooperate with the threads A in the usual and well known manner.

t, is the carrier, the pivotal axis of which is indicated at C'.. The carrier C is provided with the usual plug spindle which rotatably supports the plug B.

Cam devices M and N are mounted at diametrically opposite points with respect to the axis of the gun A. The cam device. M is situated on the side of the axis of the gun remote from the hinge of the carrier 0 and comprises a plate or bracket 10 suitably secured to the plug B. This bracket 10 is rovided with a ca n face 11 which projects into one of tli'e blank spaces B thereby enabling the bracket to be strongly implaced and in addition materially diminishes the portion of the bracket which projects beyond the rear face. of the plug. Mounted on the bushing A is a bracket 12 which carries a pin 11'. Rotatably mounted on this pin 13 is a roller 14 adapted to cooperate. with the cam face 11. The longitudinal axis of the pin 13 is disposed substantially in a line extending through the pivotal axis C of the carrier C. As a result of this construction it will be obvious that the axis of rotation of the roller 14 is also disposed substantially in a line extending through the axis C, and also at an angle to the breech face of the gun and the rear face of the plug. It will be noted that when I use the term substantially I mean that the axis of rotation of the roller 14 is either disposed in a line extending through the pivotal axis of the carrier or approximately in such a line. By this construction I am enabled to avoid skidding of the roller'14 on the cam face 11 and obviate wearing of the cam face and loss of power due to the sliding action of the roller which wear and loss of power always occurs in structures where the elements of the cam and roller surface are parallel to the breech face and the pivot of the swinging mechanism is not in the plane of the breech face. The contact face 11 of the bracket 10 is extended as at 11 so that the roller 14 will remain in engagement with said face after the cam action ceases and until the plug has'substantially completed its rotation. By providing this extension of the contact face of the cam I am enabled to first arrest the whirling movement of the plug about the hinge of the carrier and then hold the plug until it has substantially completed its rotation. If this whirling movement were not arrested the forward end of the plug would fly or spring toward the hinge side of the gun and strike thercagainst. By maintaining the roller 14 in engagement with the contact face of the bracket 10 until the plug has substantially completed its closing rotation I prevent the plug and bushing threads from chattering. In other words the forward slopes of the plug threads never strike or bear hard against the rear slopes of the threads on the breech bushing. As the forward slopes of the plug thread and the rear slopes of the breech bushing threads are relatively small it will be obvious that if they come together in hard contact a wedge biting action takes place which makes the plug hardto rotate.

The cam device N comprises a bracket 15 suitably secured to the rear face of the breech lug B and provided with a cam face 16 whic latter projects into an unused blank space E. The threads A of the bushing A on the side adjacent the hinge of the carrier 0 are cut away at the rear end of the bush{ ing as at 17 to provide the necessary clear-'- ance to permit swinging of the plug B. Mounted in the bushing A is a pin 18 one end of which projects into the cut away portion 17 and has rotatably mounted thereon a roller 19 adapted for cooperation with the cam face 16 in the usual well known manner. The axis of rotation of the roller 19 is disposed substantially in a line extending through the pivotal axis C of the carrier, while said axis of the roller is disposed at an angle to both the breech face of the gun and the rear face of the plug B. It will be noted that the roller 19 is disposed in a space that must be provided to permit swinging of the plug and therefore the mounting of the roller requires substantially no additional designing of the parts of the.

gun over what would ordinarily be resorted to. It will be noted that the axis of the pin 18 is at an angle to the axis of the pin 13 which condition renders it a comparatively easy matter to provide the recess in the bushing A for receiving the pin 18 in that such recess can be cut without employing a tool with a special head.

In operation it will be apparent that as the plug B is swung into the breech the rollers 14 and 19 will simultaneously and respectively engage the cam faces 11 and 16 and cooperate therewith to translate the swin ing movement of the plug into rotary looking movement. By employing two cam devices disposed diametrically opposite I eliminate the tendency of a single cam device to lift or lower the plug during cam action and the elimination of this tendency removes the cause which heretofore has resulted in cutting of the gas check seat of the gun by the gas check rings. By employing oppositely disposed cams which operate simultaneously I also eliminate the stress and friction at the plug spindle on the carrier which is present in the use of a single cam device, for the reason that one device pushes up on the plug while the other pushes down and in this way the plug is balanced during rotation under the influence of the cam devices.

What I claim and desire to secure by Letters Patent is 1. In a gun, the combination of a swing ing carrier, a rotatable breech plug, and a cam device for rotating the plug as the latter is swung into the breech, said device including a cam face and a roller, one of which is mounted on the gun and the other on the plug and the axis of rotation of the roller being disposed at an angle to the breech face of the gun and in a line extending substantially through the pivotal axis of the carrier.

2. In a gun, the combination of a swinging carrier, a rotatable breech plug, and a cam device for rotating the plug as the latter is swung into the breech, said device including a cam face and a roller, one of which is mounted on the gun and the other on the plug, the axis of rotation of said roller being disposed at an an le to the rear face of the breech lug an in a line extending substantially t rough the pivotal axis of the carrier.

3. In a gun, the combination of a swinging carrier, a rotatable breech plug, and a l cam device for rotating the plugias the latter is swung into the breech. said device including a cam face disposed on the plug and a roller disposed on the gun having its axis of rotation at an angle to the breech face of the gun and substantially in a line extending through the pivotal axis of the carrier. a i

4. In a gun, the combination of a swinging carrier, a rotatable breech plug having interrupted threads and resulting blank spaces bet\veen\the threads. and a cam device for rotating the plug asithe latter is swung into the breech. said device including a cam mounted on the plug and extending into a blank space between the plug threads and a roller mounted on the gun for cooperation with the cam. the. axis of rotation of said roller being at an angle to the breech face of the gun and substantially in a line extending through the pivotal axis of the carrier.

In a gun, the combination of a swinging carrier. a rotatable breech plug, a breech bushing. cooperating threads on the plug and bushing, the threads on the bushing .at the hinge side being cut away to provide clearance space for swinging the plug, and a cam device for rotating the plug as the. latter swings into the breech, said device including a cam on the plug. and a roller on the bushing and disposed in said clearance space.

6. In a gun, the combination of a swinging carrier, a rotatable breech plug. and oppositely disposed cam devices for rotating the plug as the latter is swung into the breech, each of said devices including a cam face and a roller one of which is mounted on the gun and the other on the. plug.

7. In a gun, the. combination of a swinging carrier, a rotatable breech plug. and oppositel disposed cam devices. for rotating the plug as the latter is swung into the breech. each of said devices including a cam face and a roller one of which is mounted on the gun and the other on the plug, the axis of rotation of each roller being disposed substantially in a line extending through the pivotal axis of the carrier.

54. In a gun, the combination of a swinging carrier, a rotatable .breech plug, and oppositely disposed cam devices for rotating the plug as the latter is swung into thebreech, each of said devices including a cam face and a roller one of which is mounted on the. gun and the other on the plug, the axes of rotation of said rollers being disposed respectively in lines extending substantially through the pivotal axis of the carrier and at an angle to each other.

ll. In a gun, the. combination of a swinging carrier, a rotatable breech-p ltyg, and oppositely disposed cam devices vor rotating the plug as the latter is cwunminto the breech. each of said devices including a cam face and a roller one of which is mounted on the gun and the other on the plug, the axis of rotation of each roller being disposed at an angle to the breech face and in a line extending substantiall through the pivotal axis of the carrier.

10. In a gun. the combination of a swinging carrier. a rotatable breech plug. and cam devices for rotating the plug as the latter is swung into the breech. said cam devices being oppositely disposed and each operating to collnteract the tendency of the other to throw the plug ofi center during their operation.

11. In a gun, the combination of a swing- 7 ing carrier, a rotatable breech plug, and a cam device for rotating the plug as the latter is swung into the. breech. said device including an element mounted on the gun and an elementmounted on the plug and engaged with the element on the. gun from the beginning ol the closing rotation of the plug until such closingrotation of the plug is substantially completed.

12. In a gun. the ombination of a swinging carrier. a rotata e breech plug, and oppositely disposed cam devices for rotating the plug. the elements ol' the cam device on the side of the gun opposite the pivot of the carrier being in engagement from the beginning of the closing rota ion of the. plug until such closing rotation of the plug is substantially completed,

13. In a gun the combination of a swinging carrier. a rotatable breech plug, a cam device for rotating the. plug disposed on the side ol the gun opposite the pivot of the calrier. said device inchiding a cam on the plug aml a roller on the gun engaged with said cam from the beginning ol the closing rota.- tion ott the. plug until the substantial complctiotn of said closing otation.

1'l. In a gun, the combination of a swinging :carrier, a rotatable breech plug, a cam device for rotating the plug disposed on the side ol the breech t'ace opposite the pivot of the carrier. said device including a cam on the plug and a roller on the gun. said -roller ((ltillU l'tllillg with the cam to first Inc part loclv'ing rotation to the plug and then hold the forward end of the plug against whipping toward the pivot of the carrier until the locking rotation of the plug is substantially completed.

15. In a gun. the combination of a" swinging carrier. a rotatable breech plug and a cam device including a cam on the plug and a roller on the gun, said roller cooperating with the cam to hold the. forward end of the plug against whipping toward the pivot of the carrier until the loclv'ing rotation of the plug is substantially completed.

16. In a gun, the. combination of a swinging arrier. a rotatable breech plug and a ISO cam device including a cam on the plug and a roller on the gun, said roller cooperating with the cam to hold the forward slopes of the plug threads out of engagement with the rear slopes of the breech bushing threads at all times during rotary movement of the plu 1%. In a gun, the combination of a swinging carrier, a rotatable breech plug and a cam device for rotating the plug as the latter enters the breech, said device including a cam on the plug and a roller on the gun,

said roller cooperating with the cam to impart locking rotation to the plug and to, hold the forward slopes of the plug threads-1 3 out of engagement with the rear slopes of the breech bushing threads at all times during locking rotation of the plug. In testimony whereof, I ailix my signature, in the presence of two witnesses.

DORSEY FROST ASBURY. Witnesses:

MARY P. CHAPIN, EDITH STOWELL. 

